1. Field of the Invention
This invention relates to a connector for use in connecting inter-timbers, inter-laminated woods, inter-stone members, inter-concrete members, or between timbers, laminated woods and stone members, concrete members and the like.
2. Description of the Related Art
In recent years, there have been developed the connectors for use in connecting between a beam and a pole plate, between a pole plate and a column, between a furring and an independent column so as to provide a labour saving and a streamlining or the work in a building such as a dwelling and the like or similarly developed a connection structure or a coupling structure so as to get a streamlining of the work.
For example, 1 the gazette of Japanese U. M. Laid-Open No. Sho 63-162008 discloses a framework jig used in a wooden framework process, 2 the gazette of Japanese U. M. Laid-Open No. Hei 2-93401 discloses a reinforcing jig at a connection part between a lower end of a column and a foundation of a framework type wooden building, 3 the gazette of Japanese Patent Laid-Open No. Hei 3-295946 discloses trap dowel jig and a lathing structure of the framework wooden building applied with the trap dowel jig, 4 the gazette of Japanese Patent Laid-Open No. Hei 2-300442 discloses a connecting structure of wooden structural material in which the wooden framework is not decomposed after connection. In these prior arts, fittings, bolts and nuts are used at the connection between the structural members.
In addition, as the connection structure, Japanese Patent Laid-Open No. Sho 63-14939, Japanese Patent Laid-Open No. Sho 63-14940 and Japanese Patent Laid-Open No. Sho 63-14941 disclose the connection structure in the wooden framework structure so as to improve a structural strength of the connection structure.
However, there were problems that the aforesaid prior art connector or connector structure required a large number of parts such as bolts, nuts, washers and the like, a troublesome fixing work was required and a lack of workability occurred when they were worked. In addition, it had other problems that the metal fitting was large in size, had a heavy weight, it lacked in a transporting characteristic and lacked in safety at a high location.
There was also another problem that an erroneous metal fitting occurred during the work, a troublesome operation was needed, an embedding of the cylinder or plug member punched at the predetermined position into a desired location and a threadable fitting of bolts into said embedded cylinder or the punched hole of the plug member was difficult, requiring a poor workability, a large number of steps of work and an extended work period.
The assembly having some timbers fixed by bolts or nuts had some problems that their fastening forces were lost in several years due to shrinkage of timbers to cause a certain looseness to be easily produced there and its physical strength was also reduced. In addition, it had a still another problem that the metallic portions such as bolts, nuts, metal fittings were oxidized by dew formation etc. to reduce durability of the assembly and also some imported timbers contained salt due to their storage on the sea, the bolts, metal fittings and the like in the assembled imported timbers were decayed by salt to deteriorate a physical strength and produce a poor durability.
In addition, at the time of occurrence of fire, the prior art assembly had a certain problem of anti-disaster in which the outer connector bolts, metal fittings etc. were melted at first, their strength could not be expected and a housing was crushed by these causes. In addition, the most serious disadvantage of the framework structure having wooden timbers consisted in a weakness at the connection part and in view of this fact, various kinds of connections or couplers have been devised by many carpenters from the ancient period to keep their physical strength in the framework, although all these structures had some problems that they were complex, required many working steps and showed a poor productivity. There was another problem that the wooden timber having a heavy timber had a less amount of production, its preparation was difficult and the beams made of wood or laminated wood having a long and large span could not be transported on the road due to a traffic regulation and the like.